1. Field of the Invention
This invention relates to clinical caloric ear testing, and more particularly to a method and apparatus for automatically coordinating and controlling the operation of a testing and diagnostic apparatus related to clinical caloric ear testing.
2. Description of the Related Art
Human balance disorders are common and they may result in serious and protracted suffering and disability. For example, a patient with Meniere's disease (recurrent aural vertigo) may experience attacks of severe vertigo, nausea and vomiting for years. Finding the specific cause of a patient's balance disorder is key to appropriate treatment. There are different conditions which manifest these symptoms, such as heart irregularities, blood vessel narrowing, brain tumor, and stroke, to name a few. Fairly often the cause originates in the inner ear.
In 1906, Robert Barany introduced a way to test the inner ear's balance reflex using warm or cool water irrigation in the ear canal (the “caloric” test), for which he was awarded a Nobel Prize. No practical method for controlling the intensity of the caloric test (analogous to controlling/setting loudness in hearing tests) was available until, in 1972, Proctor and Dix reported a new technique, the “temperature switching” caloric (TSC) test. In this test, the caloric stimulus intensity acting on the inner ear was controlled by switching the temperature of the caloric irrigation at specific times, in keeping with physical and mathematical models of heat flow in the temporal region about the inner ear. A clinical TSC test system, described in U.S. Pat. No. 4,106,496 to Proctor et al., incorporated fully herein by reference, was subsequently developed for vestibular function diagnosis and is still in use today.
Prior art methods provide for control and adjustment of the alternation between the two temperature fluids by use of an electrical timer, and include temperature sensors in the nozzle of the fluid delivery device which send temperature information to a meter or recorder. However, in the prior art, the processes of adjusting the timing and of inputting testing parameters relative to a particular patient, for example, all must be performed manually by operator input prior to each test. Further, processing of the data resulting from the testing must also be performed manually. Accordingly, it would be desirable to have a method and apparatus which would enable more precise measurement and control and would also allow the storage and retrieval of patient data for use in setting up and adjusting the test procedures and for research purposes.